One-pot synthesis of α-diazo-β-hydroxyesters under phase-transfer catalysis and application to the catalytic asymmetric aldol reaction

The one-pot (three steps) synthesis of α-diazo-β-hydroxyesters from tosyl chloride under phase-transfer catalysis is described. The catalytic asymmetric aldol reaction between a diazoester and aldehydes was also investigated and gave moderate to good enantioselectivity.